IN some ways, climate change isn’t really that difficult to get our heads around. It’s fairly straightforward.

If we emit another 565 more gigatons of carbon dioxide into the atmosphere we can expect the global temperature to increase by two degrees Celsius.

Anything higher would mean catastrophe for life on earth.

But if all the fossil fuels that global corporations currently have in their reserves were burnt, they would add another 2,795 gigatons of carbon dioxide to the atmosphere – five times the safe maximum.

And those corporations plan to burn it all. If fossil fuels are removed from the ground they will be used.

That’s one reason why the proposed new coal mine in west Cumbria should not go ahead.

At a time when we should be moving away from fossil fuels as fast as we can, we would be heading in the wrong direction and pressing hard on the accelerator.

What we should be doing instead is expanding green energy. And the most effective and cheapest way to do that is to build more onshore wind turbines.

Not everyone likes them. Some say they should be put out to sea, where it is often windier. It is to be hoped that we’ll see more offshore windfarms in the future.

But onshore windfarms can be built much more quickly and efficiently.

Electricity from onshore wind is also 20 per cent cheaper than offshore, which in turn is cheaper than nuclear or gas.

And it could potentially produce enough power for 7.7 million homes.

The most common objection is that they are an eyesore. David Cameron’s government tightened the planning rules for onshore wind developments in 2014 – effectively putting a halt to them – for fear of upsetting Tories in rural areas who didn’t want them in their backyards.

But they don’t have to spoil the countryside. A study by the University of Aberdeen shows that there is plenty of land, for example next to train lines and motorway routes – hardly Areas of Outstanding Natural Beauty – that could be used for wind turbines. The stretch of the M6 between Carlisle and Penrith always seems particularly windy.

Some point out that birds and bats are killed by wind turbine blades. But fossil-fuelled power stations are responsible for far more bird deaths.

Everybody likes a nice view. Everybody also likes electric lights, fridges, freezers, TVs, radios, computers, heaters, stereos, mobile phones and increasingly electric vehicles – among other things.

There were once endless objections to electricity pylons and many wanted cables put underground, especially in the Lake District. But it was far cheaper to suspend them overground, and they are pretty much accepted now. If we want electricity we have to have power stations and cables.

Whether or not they are a blot on the landscape is of course highly subjective. Personally I find them rather elegant, and somehow reassuring to know that the electricity that we all need is being created with no cost to the environment.

But even if you disagree, is an onshore windfarm more of an eyesore than a coal-fired or nuclear power station? I’d sooner have a windfarm near my home than either of those.

It’s a good thing that Rishi Sunak turned up to the Cop 27 climate summit and showed he was serious about the most serious threat to life on earth.

And it was encouraging to hear him say, in his first international speech there, that we need to “act faster” on renewable energy, calling it “both a moral responsibility and an economic necessity”.

If he really means it then he should lift the moratorium on onshore windfarms immediately.

A lot of attention was being paid at Cop 27 to the question of “loss and damage” compensation, and whether the countries that grew very rich through burning fossil fuels should direct money towards the poorer nations that did almost nothing to warm the planet, but are suffering some of the worst consequences.

To borrow the prime minister’s phrase, I would say it was both a moral responsibility and an economic necessity.

But the least we can do is stop adding to the problem.

Mr Sunak seemed impressive at first, but the gloss is coming off him already. He made some bad cabinet appointments and he’s often flustered and repetitive at Prime Minister’s Questions.

Maybe he only seemed impressive when standing next to Liz Truss and Boris Johnson, our worst and second worst prime ministers of recent times.

But if Mr Sunak were to perform a U-turn on the windfarm ban, then it would lift him, at least slightly, in my estimation.